1. Field of the Invention
The present invention relates to a tape for encasing chip-form electronic parts. More particularly, the invention relates to a tape for encasing electronic parts wherein a cover tape can be peeled from a carrier tape smoothly and automatic mounting of the chip-form electronic parts can be practiced with high efficiency.
2. Discussion of the Art
A tape for encasing electronic parts comprising a carrier tape and a cover tape pasted thereon that is suitable for so-called automatic mounting work, i.e., automatically incorporating chip-form electronic parts into the base of a printed circuit board, is disclosed in Japanese Patent Application Kokai (Laid-Open) No. 60-63995. That application discloses a tape for encasing chip-form electronic parts comprising a tape-form body (carrier tape) having a plurality of through-holes for encasing electronic parts (recesses for encasing electronic parts) and a plurality of guide perforations, a cover sheet (cover tape), and electronic parts encased in each of the recesses.
Previously in tapes for encasing electronic parts, a film made of polyester resin, such as polyethylene terephthalate (PET), was used as the cover tape. In a tape for encasing electronic parts wherein the PET film is pasted onto a carrier tape with an adhesive, the peeling of the cover tape could not be effected smoothly because the uniformity of the peeling adhesivity of the cover tape pasted onto the carrier tape was difficult to control. That is, the carrier tape was often subjected to unnecessary vibration during automatic mounting of electronic parts or during incorporation of the electronic parts into electronic instruments one by one while the cover tape was being peeled off. As a result, the electronic parts could not be incorporated exactly into the desired positions, and electronic parts ran out of the recess, and in some extreme cases, were lost.